Hi ThomasM,   I see from your other post you are using IOS 11.  I've done some looking into this and found the following post from Dropbox and in the comments they state: 'Support for the Files app will be coming next week in a new IOS app for Dropbox.'   There are also other reports on their forum of this feature not working.  I suspect Dropbox will release an update at some point this week to support the Files App.   With pCloud when i access that in the Files App (outside of Affinity Photo) i just get a message saying 'pCloud does not currently support opening file for editing.'  So looks like pCloud need to update their app to work with IOS 11.